Material treating furnace



Feb. 9, 1932.

S. KNEASS. JR

MATERIAL TREATING FURNACE Filed May '11, 1929 2 Sheets-$heet INVENTORFeb. 9, 1932. 5, KNEASS, JR 1,844,094

MATERIAL TREATING FURNACE Filed May 11, 1929 2 Sheets-Sheet 2 INVENTORPatented Feb. 9, 1932 UNITED STATES STEICKLAND KNEASS, JR., 0FSEWICKLEY, PENNSYIiVANIA, ASSIGNOR TO COSTELLO ENGINEERING COMPANY, OFPITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA MATERIALTREATING FURNACE Application filed May 11, 1929. Serial No. 362,161. I

This invention relates to material treating furnaces, and isparticularly useful for no rmalizing or annealing material such as stripor wire, although it has numerous other applications.

In furnaces as ordinarily constructed, the material is passed throughthe furnace n a horizontal direction on rollers or other supportingmeans. The material is necessarily rubbed to some extent and under theheat conditions existing in the furnace, the quality of the surface islowered. This is partrc: ularly objectionable in certain classes ofsheets.

I provide a furnace wherein the material is passed therethrough in avertically extending direction. Preferably 1t 1s passed downwardly andis arranged to be out of contact with any supporting surface through asubstantial part of the heated Zone. A plurality of strips of materialmay be handled in the same furnace. I preferably employ straighteningmeans through which the material passes on its way to the furnacechamber. as this insures that the material Wlll follow a strai ht linepath and that different strips will not rub on one another.

Heating means is provided, preferably adjacent the inlet. In order toconserve heat, a heat exchanger is placed adjacent the furnace outletand I preferably arrange for some of the combustion gases to passthrough the heat exchanger so as to maintain a nonoxidizing atmospheretherein. Means is also provided for delivering the various strips ofmaterial in different paths. This is preferably accomplished byemploying a set of guide rolls arranged in staggered relationship.

In the accompanying drawings which illustrate the present preferredembodiment of my invention as applied to a furnace for treating metalsheets Figure 1 is a vertical sectional view taken through a furnace,

Figure 2 is a vertical section taken at right angles to the section ofFigure 1,

Figure 3 is a horizontal section taken on the line IIII1I of Figure 2,and

Figure 4 is a horizontal section taken on the line IV-IV of Figure 2. 7

F igure 1 shows a furnace comprising a heating chamber 2 having a top 3and a bottom 4. -The top and the bottom are provided with slits 5through which sheet metal may pass The sheet metal to be treated issuppliedin "coils C nounted on unreeling' spindles of straighteningrolls 7 is provided for each metal strip so as to remove thecurl fromthe metal and insure that it will take a straight line path through thefurnace chamber. Combustion chambers 8 are arranged at each side of thefurnace chamber adjacent the top 8. Each of-these chambers isprovidedwith burner openings 9 and is separated from the chamber-proper by abridgewall 10.- The hot combustion gases pass to the furnace chamber 2and downwardly therethrough to outlets 11 immediately above the bottom 4of the furnace. The outlets 11 are connected to stack passages 12. Thisarrangement insuresthat the cold sheets will come into contact with hotcombustion gases and that, therefore, oxidation will be minimized oreliminated.

Afterthe sheets travel through the furnace 2 they pass into a coolingchamber 13 having a heat exchanger 14. therein. The heat exchanger 14 ismade in spaced hollow sections 23 between which the sheets pass. The sections are each provided with baffles 15 so as to guide the airtherethrough, as shown by the arrows. The cooling air enters at 21 and 6above the furnace chamber 2.-A set leaves at 22. The heated air may beused for combustion at the burner openings 9 by the use of a conduit 18which conducts the air to openings 19 near the said burner openings 9. Adamper 20 may be inserted in the conduit 18 to control the air flow tothe burners.

Stack openings 16 are provided in the cooling chamber 13 below the heatexchanger 14. These stack openings, as well as the stack openings 12,are provided with suitable dampers 17 whereby the flow of gases may beregulated. This arrangement permits of drawing a desired amount of thecombustion gases downwardly through the cooling chamber, thusmaintaining an'inert non-oxidizing atmosphere therein. The heatexchanger 14 is of sufficient capacity to cool this gas, as Well as themetal sheets.

The sheets pass downwardly through slits in the bottom 18 of the coolingchamber 13 and each pass over a guide roll 19. The guide rolls arearranged in staggered relationship so that the treated metal isdischarged in different paths, as shown in Figure 1.

WVhile Ihave described and illustrated the present preferred form of myinvention, it

will be understood that it is notthus limit-ed,

as it may be otherwise embodied or practiced within the scope of thefollowing claim:

I claim An elongated heat treating furnace having end openings for theentrance and exit respectively of the material to be treated, means forpassing said material continuously through the furnace from one end tothe other, a combustion chamber, means at the entrance end of thefurnace for introducing hot products of combustion from said chamberinto intimate contact with said'material, means for withdrawing aportion of-the combustion products between the ends ofthe furnace, meansat the exit end of thefurnace for cooling the materiahasaid meansincluding independent passages forsaid material and an air stream, andmeans for conducting said air streamto the combustion chamber.

In testimony whereoflhave hereunto set myhand.

- STRICKLAND KNEASS, JR.

